Introduction to the Extrusion Process Summary

INTRODUCTION TO THE EXTRUSION PROCESS SUMMARY

• Basic description of a twin screw extruder • Introduction to the extrusion process

• Preconditioning

• Thermomechanical Cooking and Expansion

. Part 1: Extrusion variables and effects on the process/product . Part 2: Screw profile design . Part 3: Die-level expansion/texturing

TWIN SCREW EXTRUDER (TSE) SINGLE SCREW EXTRUDER (SSE)

FOOD EXTRUSION- COLD PLASTICS EXTRUSION COOKING PROCESS IN SSE PASTA PROCESS IN SSE 30’s 40’s 50’s 60’s 70’s 80’s 90’s 00’s

FOOD PAPER PULP EXTRUSION PLASTICS PROCESS EXTRUSION- PROCESS POROSIFICATION IN TSE COOKING IN TSE IN TSE IN TSE

. Extrusion is a thermomechanical process consisting in forcing a product through a small size hole, under pressure and temperature thanks to a mechanical device type Archimede screw.

. Functions of an extruder: feeding, conveying, compressing, cooking, shaping...

. Expansion is due to the water flash off caused by the pressure difference out of the die.

EXPANSION SHRINKAGE

DIE

MELT

MIXING

EXTRUSION COOKING

SHAPING

Heating Gearbox collars

Motor Operator Barrel modules Interface Die assembly Cooling circuit

The module, which houses the screws, is comprised of several modular parts Different types available : . AB1 (First feeding barrel) . FER (closed barrel) . VAP (vapour injection barrel ) . ABF (lateral feeding barrel) ….

FER

Cooling circuit outlet Feeding barrel Electric Resistance

Temperature sensor

Cooling circuit inlet

INDEPENDENT temperature control (cooling/heating) of each barrel of the extruder

BC: Serial flow EV: Parallel flow

Cooling fluid temperature Cooling fluid temperature

inlet 12

outlet inlet 1 Barrel axis Barrel axis 12 pass outlet 2 pass

- Homogenisation of the temperature ADVANTAGES: - Improvement of the thermal exchange

FLOW FLOW

CO-ROTATING COUNTER-ROTATING

Interpenetrating → SELF-CLEANING

C2F Screw elements mounted on splined shafts:

BL22 . Modular screw profile . Perfect continuity of the profile C1F

Wide range of screws available to optimize the thermomechanical cooking of the melt

VERY EFFICIENT MICRO-MIXING :

Gap barrel-screws Intermeshing zone

Flow

Evolum Key Aspects With improved benefits

Larger operation window: Greater productivity: Torque power-RPM (Output: + 30-40%)

Optimal Cooling Advanced Thermal Control

Direct Scaling Hygienic Design

. Continuous auto-adjustment to the recipe and variations = Self-learning device . Optimum response when

Perfect response disturbance, no compromise PID response between response time and ATC response stability

. Stability improved by 70 % Temperature Time . Energy saving up to 20 % No additional PID settings with ATC

* Availability depending on PLC brand

. Innovative hygienic design for optimal cleanability

. Use of open profile instead hollow body for main frame and all structures (beam excepted)

. Spacing between components

. Open corners

. Stainless steel cooling pipes or armoured flexible with elastomer cover

. Visual management

. Fitsys+ V2: user-friendly

Historical data management

Automatic Start-up & Shutdown

. Process optimization via repeatable start sequences . Independent of the operator know-how

. Optimized lifetime on screws & barrels . Recipes management

. D: Direct opening or H: 2-step opening Hydraulic barrel opening for easy maintenance and cleaning

. M: Modular configuration & 2-step opening Ideal for R&D purpose Materials

Paint coating RAL 9006 Stainless steel

. Proven features of the EVOLUM® Extruder . High capacity due to increased Do/Di effect . Heat transfer management thanks to Advanced Thermal Control . Food safety achieved with a specific Hygienic Design

Range EV44+ EV56+ EV72+ EV93+ EV119+ EV153+

DIRECTLY EXPANDED= DX

NON-EXPANDED / INDIRECTLY EXPANDED

RAW MATERIALS STEAM WATER DEGASIFICATION WATER / LIQUIDS STEAM

TEXTURED Motor (Em) PRODUCT

PRECONDITIONING THERMOMECHANICAL COOKING TEXTURING - Pre-humidification and heating of (Et & Em) - Expansion: Mechanism raw materials - Starches: loss of crystallinity and of the whole dependent on the flash off state of the starch granules, depolymerisation, - Biopolymer preparation (glass-rubber - Die face cutting or remote formation of the amylose-lipid complex transition) to improve the process cutting - Proteins : denaturalisation and aggregation, (max flow; shearing, product quality, possibility of forming covalent bonds wear, etc.)

Textured Vegetable Protein

Pet Food and Fish feed

Motor EXPANSION

Conveying & Compression Mixing & Cooking Compression, Shaping & Section Section Texturing Section P

Axial Distance MULTIPLE SECTIONS OF A SERIAL PROCESS thanks to the various restrictions generated by the work of the screws. High mixing levels, heat transfer and shearing

SEI

LEI

Water evaporation

. Airy texture - cellular structure - crunchy texture . Expansion or texturing (cell structure vs. fibrated structure) . Expansion factor > 1.5 to 5. . Low density : • Snacks and cereals: from 30g/L to 150 g/L • Pet food and Fish feed: from 300g/L to 700 g/L

350 – 1 700 kg/h

Raw material preparation Twin screw extruder Belt dryer Coating device

. Pellet snacks . Extruded flakes . Ingredients . Fruit pieces/rolls . Cheese . Pet treats . High Moisture Extrusion Cooking (HMEC)

RAW MATERIALS VAPOUR

WATER DEGASIFICATION WATER / LIQUIDS VAPOUR

TEXTURED

Motor (Em) PRODUCT

Conveying & Compression, Mixing E& tCooking Cooling Compression Section Section Shaping & Section Texturing Section P

Axial Distance

. Dense Structure . Limited or non-existent expansion • Expansion factor < 1.5 • High density (> 600 g/L) . May need additional treatment

250 – 1 200 kg/h

Twin screw Conveyor Tempering Flaker Dryer Coater Cooler extruder & nib cutter drum toaster dryer optional 200 to 2000 kg/h

Twin screw extruder Cutter Cooler Dryer 200 – 1 200 kg/h

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